Melt-blown nonwoven

One of the important aspects of the development of P-plastomers was the expectation that these materials were amenable to plastics processing such as fiber and film formation and yet would yield soft elastic fabrication. This combination was hitherto unknown [24]. The formation of nonwoven fabrics including spun-bond and melt-blown nonwoven fabrics as well as their laminated forms has been documented. Similarly, cast film operation to form elastic monolithic films or composite structures which are not only amenable to these processes, but also to a variety of postfabrication processes have been described. 

Melt-blown nonwoven fabric TPX are used as separator materials. They are thin, but sufficient in mechanical strength and possess superior shape retention at elevated temperatures. 

However, melt-blown nonwoven fabrics with a microscopic variation of basis weight in different parts are a further drawback. The variation changes little even after the melt-blown nonwoven fabrics are pressed or embossed with metal rolls or press plates. Accordingly, the fabrics or pressed products, when used as separators, cause a microscopic nonuniform passage of electrolytes or ions in different parts of the membrane. 

G. S. Bhat, V. Narayanan and L. C. Wadsworth, Dimensionally Stable Polyester Films, Fibers, Yarns and Melt Blown Nonwovens, U.S. Patent 5,753,736 (issued May 19, 1998). 

G. S. Bhat, Y. Zhang, L. C. Wadsworth, and M. Dever, "Processing of Post-Consumer Recycled PET into Melt Blown Nonwoven Webs, International Nonwovens Journal, 3,6 54-61 (1994). 

Recent studies have indicated direct correlations between surface area and catalytic activity of metal oxide sensors (Li et al. 1999). Therefore, it is evident that incorporating catalytic particles by coating techniques may affect surface area and catalysis. Studies by Lee and Bhat (2003) have demonstrated that by incorporating small amounts of electrospun nanoflbers in spun-bond and melt-blown nonwovens, barrier properties such as flitration efficiency and air permeability can be improved. 

Another example of melt-like processing of cellulose in NMMO/water [35] is the so-called melt-blown nonwovens process, which is widely used for conventional thermoplastics. The basic principle is shown in Figure 3.9. As in the thermoplastic case, filaments are produced... 

JP Patent 11,117,164, Biodegradable nonwoven laminates of melt-blown nonwoven fabrics of aliphatic polyester fibers and spnnbonded nonwoven fabrics of urethane bond-containing butylene succinate copolymer fibers , Kawano, Akitaka Kin, Kasue, 1999. 

For special applications, polybutylene terephthalate (PBT) is another fiber alternative in the polyester family, especially in melt blown nonwovens for filters. Properties of the typical three polyesters are shown in Table 2.26. 

Many hltration nonwovens are so-called dual density . For example, needle-punch and melt blown nonwovens are used together in composite hlters [16]. 

There are two parts in this chapter. In part 1 (section 8.3), the above-mentioned models, i.e. the ANN model and statistical model are used to predict the fiber diameter of melt blown nonwoven fabrics from the processing parameters. The results are expected to give an indication of the relative roles of these models in predicting the fiber diameter of melt blown nonwoven fabrics. In part 2 (section 8.4), to meet the demand of establishing small-scaled ANN models, an input variable selection method was developed to help model the structure-property relations of nonwoven fabrics for filtration application. The structural parameters were selected by utilizing this method. The ANN models of structure-property relations of nonwovens were established. This section will establish a reasonably good ANN model that can generalize well and consider more structural parameters as the model inputs. 

ANN AND Statistical Models for Predicting Fiber Diameter of Melt Blown Nonwoven Fabrics... 

The fiber diameter is a key property of the melt blown nonwoven fabrics and strongly affected by the processing parameters such as polymer flow rate, initial air velocity, and die-to-collector distance. In this section, ANN and statistical models were employed to predict the fiber diameter from the processing parameters. 

The ANN and statistical method are used to predict nonwoven properties from the processing parameters and structural characteristics of nonwoven fabrics. The ANN and statistical models are established for predicting the fiber diameter of melt blown nonwoven fabrics from the processing parameters. The results show that the ANN model yields very accurate prediction (average error of 0.013%) and a reasonably good ANN model can be achieved with relatively few data points. Statistical models may be used for intuitive or qualitative analysis. 

With this process, spun-bonded and melt-blown nonwovens can be produced and combined. This aiiows the manufacturing of multilayer composite nonwovens in a... 

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